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Alkali Metal Doping for Improved CH₃NH₃PbI₃ Perovskite Solar Cells.

ABSTRACT: Organic-inorganic hybrid halide perovskites are proven to be a promising semiconductor material as the absorber layer of solar cells. However, the perovskite films always suffer from nonuniform coverage or high trap state density due to the polycrystalline characteristics, which degrade the photoelectric properties of thin films. Herein, the alkali metal ions which are stable against oxidation and reduction are used in the perovskite precursor solution to induce the process of crystallization and nucleation, then affect the properties of the perovskite film. It is found that the addition of the alkali metal ions clearly improves the quality of perovskite film: enlarges the grain sizes, reduces the defect state density, passivates the grain boundaries, increases the built-in potential (V_bi), resulting to the enhancement in the power conversion efficiency of perovskite thin film solar cell.

SUBMITTER: Zhao W

PROVIDER: S-EPMC5827644 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Alkali Metal Doping for Improved CH3NH3PbI3 Perovskite Solar Cells.

Zhao Wangen W Yao Zhun Z Yu Fengyang F Yang Dong D Liu Shengzhong Frank SF

Advanced science (Weinheim, Baden-Wurttemberg, Germany) 20171221 2

Organic-inorganic hybrid halide perovskites are proven to be a promising semiconductor material as the absorber layer of solar cells. However, the perovskite films always suffer from nonuniform coverage or high trap state density due to the polycrystalline characteristics, which degrade the photoelectric properties of thin films. Herein, the alkali metal ions which are stable against oxidation and reduction are used in the perovskite precursor solution to induce the process of crystallization an ...[more]

PMID: 29610718

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